MINNEAPOLIS (AP) — The FBI is investigating 13 threatening letters containing a white powder that were mailed to Twin Cities area businesses.
Eight of the letters were addressed to Home Depot stores in the metro area. Five were addressed to Renewal by Andersen businesses.
The Minnesota Department of Health lab analyzed the white powder in the first 12 letters and found it was sodium bicarbonate, a harmless substance. The powder in the last letter received has not been analyzed yet.
The first letter was received last Friday and the most recent letter was received Thursday.
The FBI says the return address on each envelope is identical. The letters are all the same and appear to be photocopied.
Anyone with information is asked to call the FBI.
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